Hi all,
I've encountered a problem with my AMD 890FX based system
and linux-2.6.35.10 (x86_64 platform).
After activating the option "IOMMU" in the mainboard's BIOS
setup, the onboard P-ATA controller "JMicron Technology Corp.
JMB361 AHCI/IDE (rev 02)" puts itself back in the PIO mode.
When loading the module, the kernel reports:
pata_jmicron 0000:06:00.1: BMDMA: failed to set dma mask, \
falling back to PIO
This results, as expected, in a much too low data throughput
between the system and the optical drives connected to the
P-ATA controller.
As soon as I deactivate IOMMU in BIOS setup, the P-ATA channel
runs in the DMA mode again. The S-ATA controllers don't seem
to be affected.
My question is: Is this a known behavior? Are there any
things I have to consider when activating IOMMU (which seems
to be AMD-Vi) on an 890FX based system? Is it a problem of
the chipset and/or the controller or is it related to a
problem in the libata area?
Some information about the affected system:
- Mainboard: ASUS M4A89TD Pro/USB3
- BIOS version: 1101 (most recent version)
- Chipset: AMD 890FX
- Processor: AMD Phenom 1090T
- Memory: 4 x 4 GB (Kingston KVR1333D3E9S/4G)
- Distribution: openSUSE 11.3
- Kernel: 2.6.35.10 (from "kernel.org"), x86_64
Earlier versions of 2.6.35.x are affected, too. I haven't
tested other kernel versions besides 2.6.35.x, yet.
If you need further information (log files, information from
"/proc", lspci, and so on), please let me know.
Thank you very much in advance for any hint!
Best regards,
Steffen
(CC'd linux-ide, Joerg)
On 12/28/2010 06:43 PM, Steffen Moser wrote:
> I've encountered a problem with my AMD 890FX based system
> and linux-2.6.35.10 (x86_64 platform).
>
> After activating the option "IOMMU" in the mainboard's BIOS
> setup, the onboard P-ATA controller "JMicron Technology Corp.
> JMB361 AHCI/IDE (rev 02)" puts itself back in the PIO mode.
> When loading the module, the kernel reports:
>
> pata_jmicron 0000:06:00.1: BMDMA: failed to set dma mask, \
> falling back to PIO
[...]
> As soon as I deactivate IOMMU in BIOS setup, the P-ATA channel
> runs in the DMA mode again. The S-ATA controllers don't seem
> to be affected.
>
> My question is: Is this a known behavior? Are there any
> things I have to consider when activating IOMMU (which seems
> to be AMD-Vi) on an 890FX based system? Is it a problem of
> the chipset and/or the controller or is it related to a
> problem in the libata area?
>
> Some information about the affected system:
>
> - Mainboard: ASUS M4A89TD Pro/USB3
> - BIOS version: 1101 (most recent version)
> - Chipset: AMD 890FX
> - Processor: AMD Phenom 1090T
> - Memory: 4 x 4 GB (Kingston KVR1333D3E9S/4G)
> - Distribution: openSUSE 11.3
> - Kernel: 2.6.35.10 (from "kernel.org"), x86_64
>
This condition occurs when the PCI API cannot set the PCI device's DMA
mask to the 32-bit value
#define ATA_DMA_MASK 0xffffffffULL
That is an unusual failure for such a modern system, which certainly can
handle 32-bit masks like that, one would think.
Jeff